1. Field of the Invention
The present invention relates to a traffic information providing system for providing a display of traffic information and, more particularly, to a traffic information providing system in which, if even one vehicle on which an on-vehicle radio transmission/reception device is mounted passes through an on-road radio transmission/reception device, detailed traffic information can be provided to other vehicles by the on-road radio transmission/reception device.
2. Description of the Related Art
FIG. 6 is a view showing a conventional traffic information providing system described in Japanese Unexamined Patent Publication No. 6-180795. Referring to FIG. 6, on an automobile 1, various sensors such as a steering sensor, a direction sensor, and a vehicle speed sensor and a transmission/reception circuit are arranged. Steering angle data detected by the steering sensor, progress direction data detected by the direction sensor, vehicle speed data detected by the vehicle speed sensor are transmitted by the transmission/reception circuit through a transmission antenna 2. Data corresponding to these data and transmitted from another vehicle are received by the transmission/reception circuit of own vehicle and then transmitted in the same manner as described above.
A reception circuit and a controller are arranged in a traffic information display device 3 installed on a road such as a curve where visibility is not good. The presence/absence of occurrence of traffic jam, an accident, or the like is checked on the basis of data received by the reception circuit through a reception antenna 4, and a display content corresponding one of display contents of a plurality of preset types is selected to display the display content on a display part 5.
Therefore, when an automobile traveling in one lane receives data transmitted from an automobile jammed in the other lane, the data received from the other vehicle and the data of the own vehicle is transmitted to the display device 3. It is determined on the basis of the data received by the display device 3 that a traffic jam occurs in the other lane, and information which informs occurrence of a traffic jam is displayed on the display part 5 to provide traffic jam information to an automobile traveling in the other lane.
In the traffic information providing system with the above arrangement, a forward traffic situation can be recognized by a backward vehicle.
However, a conventional traffic information providing system with the above arrangement has the following problems:
(1) If there is no oncoming vehicle, information of a forward section of a display device 3 cannot be obtained. PA1 (2) Since a relative speed is high in inter-vehicle communication, a high-speed data communication means is required. PA1 (3) If the distance between display devices 3 is long, a large amount of data of each vehicle must be transmitted and received to obtain detailed information in the section between the display devices 3.